Transmission performance of uplink SU-MIMO (single user multiple-input multiple-output) transmission may be improved by selecting a proper pre-coding matrix indication (PMI).
A base station receives a sounding signal periodically sent by a terminal. After receiving the sounding signal, the base station uses a pilot signal to parse the sounding signal to obtain a channel response, performs data processing on the obtained channel response according to a PMI selection criterion to select a proper PMI from a set of candidate PMIs, and delivers the selected PMI to the terminal through a physical downlink control channel (PDCCH).
In the process of implementing the foregoing solution, the prior art has at least the following problems:
In the prior art, the PMI selection is performed based on sounding measurement. Such issues as whether a terminal supports sending of a sounding signal, a sounding measurement period, or frequency band resources affect accuracy of the PMI selection, and thereby affecting performance gain of SU-MIMO.